1. Field of the Invention
The present invention relates to a pharmaceutical composition comprising a butyrophenone compound which is useful as a cataplasm.
2. Description of the related Art
Butyrophenone compounds have antipsychotic effects by means of inhibiting dopamine action. The butyrophenones are mainly used for the treatment of schizophrenia. Further, the compounds have antiemetic effects by acting on chemoreceptor triger-zones.
Recently, adverse reactions to cancer chemotherapy such as, for example, nausea and emesis, have become clinical problems. For the treatment of such adverse reactions, amtiemetics have been frequently used. In general, since the antiemetics are administered orally, the administration of antiemetics has various disadvantages as follows:
(a) it is necessary for patients to take the drug at least three times a day, PA1 (b) it is difficult to control the blood level of the drug, which results in the possibility of causing extrapyramidal syndromes in the patient such as akathisia and psychotic disorders such as, for example, anxiety and nervousness when the blood level of the drug increases over a certain level, and PA1 (c) it is difficult to administer the drug orally to some patients who vomit frequently during intervals of continuous vomiting.
One attempt to solve the above-mentioned problems was to administer the drug percutaneously in a form of an external preparation. An example of such an external preparation is that using a gel-type vehicle comprising water and a water-soluble polymer such as, for example, hydroxypropylcellulose and polyvinyl alcohol. However, if the external preparation comprising the gel-type vehicle is prepared in a form of a pasty composition dispensed from a tube, it is difficult to determine a single dosage to be administered and the area of the skin of a patient to be applied with the preparation. On the other hand, if the external preparation using the gel-type vehicle is prepared in a form of a tape composition to be applied on the skin of a patient, the manufacturing cost becomes too high due to its complicated structure. Another example of the external preparation is a cataplasm comprising the drug dispersed or dissolved in a vehicle such as, for example, a rubber-based adhesive, an acrylic adhesive, a silicone adhesive, or a water-soluble polymer. However, these cataplasms are not able to attain high blood level of the drug due to a low percutaneous absorption of the drug. In addition, the use of the cataplasm comprising a water-soluble polymer is not convenient since the structure of drug-containing layer cannot be maintained because of sweating during the application of the cataplasm.